1. Field of the Invention
The present disclosure relates to heat exchangers, condensers, and the like, and more particularly to systems and methods for cleaning tubesheets in heat exchangers, condensers, and the like, e.g., while operating or shutdown without requiring disassembly.
2. Description of Related Art
Shell and tube heat exchangers can be used for exchanging heat between a first fluid in the shell, and a second fluid in the tubes passing through the shell. This arrangement can be used simply for heat exchange, but one specific application is in condensers such as used in steam powered systems. In such an application, spent steam enters the shell and flows over the tubes. There is a cool flow of water or other coolant passing through the tubes, and as heat transfers from the steam into the water through the tube walls, the steam condenses into the bottom of the shell or hotwell. Condensate from the bottom of the shell can then be recycled through the steam cycle in a closed system, or discharged into the environment in an open system.
Typically the water passing through the cooling tubes is not distilled or purified water. Instead, it is common to use sea water, river water, or water otherwise drawn from the environment. Impurities and entities such as minerals, algae, biological organisms, and the like, can deposit themselves and can accumulate within the heat exchanger tubes, and on the tubesheets at the entrance and exit of the tubes.
The accumulation of these deposits, known as fouling, in the tubes and tubesheets must be addressed or else the performance of the heat exchanger will diminish. In a steam powered plant, a shutdown of three or more days may be required in order to remove the deposits from the tubes and tubesheets. Some solutions to this problem have been used, such as systems that employ sponge ball cleaners that circulate through the tubes. While such systems may allow for cleaning in line with operation of the heat exchanger, they inevitably add complexity issues to the operation.
Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for improved cleaning of heat exchangers, condensers, and the like. The present disclosure provides a solution for this need.